Justification:Bulimulus nesioticus is endemic to Santiago Island in the Galápagos Islands. It is known from six subpopulations on the island, with a range of suitable habitat less than 200 km². Population size is known to fluctuate widely from year to year, possibly due to climate changes in climate as a result of El Niño cycles. The main threat to the species is destruction and/or alteration of habitat by introduced goats.

Destruction and/or alteration of habitat by introduced goats is the main threat to the species. There is an established population of the invasive little fire ant, Wasmannia auropunctata, on the island (Silberglied 1972).